This invention generally relates to computers and more specifically relates to multiple functionality associated with an ON/OFF pushbutton switch of a computer.
Computers typically utilize an ON/OFF pushbutton switch to initiate a power up sequence from a powered down (OFF) state and to power down from a powered up (ON) state. Depressing and releasing the pushbutton when the computer is OFF causes a power up sequence to be initiated. After the computer has successfully booted and reached an operational state, depressing the pushbutton for 4 seconds will cause the computer to power down regardless of the condition of a software application that may be running. Using the pushbutton to power down the computer may be necessary in the event of an irrecoverable error by the application software or the operating system. Such ON/OFF pushbutton operation satisfies requirements of the Advanced Configuration and Power Management Interface (ACPI) standard.
Laptop computers, in addition to having an ON/OFF button, are typically provided with a sleep/wakeup button. After the laptop computer has successfully booted, the user may employ the sleep/wakeup button to cycle the computer between a sleep state that conserves battery power and an active (awake) state in which application programs are made available to the user. There exists a need as will be more filly described in the Detailed Description section below.